Assessing Pretransplant and Posttransplant Therapy Response in Multiple Myeloma Patients

Abstract

Multiple myeloma (MM) is a hematologic cancer defined by an abnormal development of clonal plasma cells in the bone marrow, releasing vast quantities of immunoglobulins and different proteins. In the majority of patients, MM remains incurable despite decades of medical improvement and a number of treatment breakthroughs. Frontline standard-of-care has little long-term success, with the majority of patients eventually relapsing, although the overall progression-free survival (PFS) has improved significantly in the last ten years. Patients who are eligible for a transplant have the highest PFS rate at 5 years, depending on medication response and other various factors that are yet to be discovered. Therefore, the current study aimed to evaluate the response to VCD (bortezomib, cyclophosphamide, dexamethasone) and VTD (bortezomib, thalidomide, dexamethasone) used as pretransplant regimens, as well as to compare responses between thalidomide and lenalidomide used as maintenance therapy posttransplant. This retrospective study was performed on a group of 105 hospitalized patients in the Hematology Department of the Timisoara Municipal Emergency Clinical Hospital between January 2016 and December 2021. Data was collected from the paper records of patients with MM who were under-followed. The treatment regimens used as induction therapy were either VCD or VTD if cyclophosphamide was contraindicated. Of the 105 patients, 27 became eligible for bone marrow transplantation. Furthermore, they received maintenance therapy which was based on either lenalidomide with dexamethasone or thalidomide with dexamethasone. Of the 62 patients treated with VTD, 17.7% were in complete remission before stem cell transplantation. Of the 43 patients treated with VCD, 37.2% were in complete remission. The 5-year mean progression-free survival (PFS) in the entire cohort was better in the group treated with the VTD regimen (31.6 vs. 27.2 months). However, in the 27 patients undergoing maintenance after ASCT, the PFS with thalidomide was 35.5 months (95% CI = 27–42), while the PFS rate in those receiving maintenance treatment with lenalidomide was 46.1 months (95% CI = 20–73). VCD proved to be superior to VTD in inducing complete pretransplant responses. Regarding maintenance therapy, patients from the lenalidomide group had superior responses compared with those under thalidomide.

Keywords

• multiple myeloma
• stem cell transplantation
• bortezomib
• thalidomide
• cyclophosphamide
• dexamethasone